One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,5)(4,6)(7,8)(9,10,13,19,14,18,26,34)(11,15,22,32,23,17,21,31)(12,24,28,36,29,16,27,37)(20,35,25,40,38,30,39,33)(1,3,5,2)(4,7,8,6)(9,11)(10,15)(12,25)(13,22)(14,23)(16,33)(17,18)(19,32)(20,27)(21,26)(24,40)(28,38)(29,39)(30,36)(31,34)(35,37)(1,4,5,8)(2,6,3,7)(9,12,26,28,14,29,13,27)(10,16,34,37,18,24,19,36)(11,20,22,39,23,38,21,25)(15,30,32,40,17,35,31,33)(2,3)(6,7)(9,11)(10,17)(12,20)(13,21)(14,23)(15,18)(16,35)(19,32)(22,26)(24,30)(25,27)(28,39)(29,38)(31,34)(33,37)(36,40) involution — undirectedA Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.